Be sure your batteries are fully charged if not you will have problems firing nails.

Check your fuel cells expiration dates. This is printed on the bottom of all style fuel cells. If the fuel cell expiration is close or pas,t you will experience not sinking of nails, misfires or not fire at all

Hot and cold weather: At high temperatures above 90 degrees F, fuel cells may overdose the amount of fuel in the combustion chamber. At low temperatures below 40 degrees F the nails may not drive nails completely, due to the fact that fuel cells loose the required propellant force.

Additional hint for cold weather keep your fuel cells and extra battery warm by keeping them in an inside pocket close to your body and rotate them around. Do not store nailer setup in the truck overnight bring indoors.